An image forming device may be categorized into a striking type, an ink jet type, and an electronic imaging type. Accordingly, the image forming device may include a ribbon printer, an ink printer, and a laser printer.
FIG. 1 illustrates an image forming device. The image forming device includes a first path 101 and a second path 102. A paper disc 103, a paper pick-up unit 104, a developing unit 105, a fixing unit 106, and a paper discharge unit 107 are sequentially arranged along the first path 101.
The paper inlet of the second path 102 is connected to somewhere between the fixing unit 106 and the paper discharge unit 107. The paper outlet of the second path 102 is connected to somewhere between the pickup unit 104 and the developing unit 105. A double-sided printing unit 108 is arranged between the paper inlet and the paper outlet of the second path 102. When the paper is printed on one side, the paper is conveyed from the paper tray 103 to the developing unit 105 by the paper pickup unit 104. The developing unit 105 transfers the developer to the front side of the paper to form an image. The paper is conveyed to the fixing unit 106, and the fixing unit 106 fixes the image on the front side of the paper. Then the paper is conveyed to the paper discharge unit 107, and the paper discharging unit 107 rotates forward to discharge the paper. When the paper needs to be printed on two sides, the paper discharging unit 107 rotates backward to convey the single-sided paper to the paper inlet of the second path 102. Then after the paper is turned over by the double-sided printing unit 108, the paper is discharged from the paper outlet of the second path 102 to the developing unit 105. The developing unit 105 transfers the developer to the back side of the paper to form another image. Then the paper is conveyed to the fixing unit 106, and the fixing unit 106 fixes the image on the back side of the paper. The paper is conveyed to the paper discharge unit 107, and the paper discharge unit 107 discharges the paper from the paper discharge unit 107.
During the above printing process, the driving part of the fixing unit 106 and the driving part of the double-sided printing unit 108 are always rotating forward. And the paper discharging unit 107 needs to rotate forward during the single-sided printing process, and rotate backward during the double-sided printing process. Thus, conventional image forming device has a driving system including a first motor and a second motor. The first motor is used for driving the driving part of the fixing unit 106 and the driving part of the double-sided printing unit 108 to always rotate in the clock wise direction. The second motor rotates forward or backward to drive the paper discharging unit 107 to rotate forward or backward, respectively. Therefore the cost of the image forming apparatus and the complexity of the control system are increased.
The disclosed system and apparatus are directed to at least partially alleviate one or more problems set forth above and to solve other problems in the art.